PROJECT SUMMARY/ABSTRACT Adolescent obesity, a preventable chronic condition that affects over 1 in 5 adolescents (ages 12-19 years) in the United States, has been linked to cardiovascular disease, diabetes, and high cholesterol. The cost attributed to adolescent obesity is approximately $14 billion annually, and obesity shortens life expectancy by up to eight years. Sexual minority adolescents (SMA; those who identify as gay/lesbian or bisexual, or who are unsure of their sexual identity) are significantly more likely to be obese and to have lower rates of physical activity and higher rates of sedentary behavior compared to their heterosexual peers. School violence (e.g., bullying and other violent acts) is associated with obesity, such that obesity risk is increased due to negative health behavior engagement in response to violent events. Given that SMA experience school violence at disproportionately high rates compared to their heterosexual peers, it is possible that school violence helps account for their higher risk of obesity. A protective school climate (i.e., a school with policies and practices that protect sexual minorities) is an important community-level determinant that has been shown to decrease sexual-minority-related school violence. Despite these known associations, few investigations have examined the relationship between school violence and obesity among SMA, and none have examined how school climate may influence this relationship. The proposed study will address these gaps through secondary analysis of cross-sectional, district-level pooled data from the Centers for Disease Control and Prevention's (CDC's) Youth Risk Behavior Surveys (from which we will obtain individual-level health behaviors and interpersonal-level school violence data) linked with the CDC's School Health Profiles (from which we will obtain community-level school climate data). Guided by an adapted Social Ecological Model, the specific aims are: (1) to examine the association between school violence and obesity and whether it differs for SMA and their heterosexual peers, and (2) to examine the association among sexual identity, school violence, and obesity and whether it differs across different levels of school climate. The proposed aims are consistent with the goals of the National Institute of Nursing Research and align with its strategic plan to support science that investigates key social and environmental factors that promote long-term wellness and prevent the development of disease across settings and the lifespan, with the goal of eliminating health disparities. To facilitate such research, the applicant will build her knowledge and skills in sexual minority health, adolescent chronic disease, and multilevel modeling and moderation analysis. With the mentorship of a dedicated and National Institutes of Health-funded interdisciplinary research team, and the resource-rich environment of Columbia University, the applicant will build a strong foundation from which to move toward her long-term goal of becoming an independent nurse scientist with expertise in obesity-related health disparities among SMA.